Display device

ABSTRACT

A display device includes: a substrate including, in a plan view, a first area and a second area; a first sub-pixel disposed on the substrate, the first sub-pixel including an emission area disposed in the first area; a second sub-pixel disposed on the substrate, the second sub-pixel including an emission area disposed in the second area; a transmission area disposed on the substrate, the transmission area being adjacent to the second sub-pixel disposed in the second area; and a sensor disposed under the substrate, the photo sensor disposed in the second area. The emission area of the first sub-pixel has a first size and the emission area of the second sub-pixel has a second size different from the first size.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. patent application Ser. No.15/495,983, filed on Apr. 25, 2017, which claims priority to and thebenefit of Korean Patent Application No. 10-2016-0122363, filed on Sep.23, 2016, which is hereby incorporated by reference for all purposes asif fully set forth herein.

BACKGROUND Field

The invention relates generally to a display device, and, moreparticularly, to a display device including a fingerprint sensor.

Discussion of the Background

As interest in displays and demand for portable information media haveincreased, research in and commercialization of display devices havebeen attracted more attention.

Recently, a display device including a touch sensor for inputting atouch of a user has been commercialized. Accordingly, the user is moreconveniently capable of using the display device through the touchsensor.

In addition, recently, a display device with a reinforced securityfunction using fingerprints has been developed.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the inventiveconcepts, and, therefore, it may contain information that does not formthe prior art that is already known in this country to a person ofordinary skill in the art.

SUMMARY

Display devices constructed according to the principles of the inventionare capable of enhancing a security function of the display device byincluding a fingerprint sensor having improved sensitivity.

In addition, display devices constructed according to the principles ofthe invention having improved fingerprint sensor sensitivity may beflexible display devices and may be capable of sensing a touch positionand a touch pressure.

Additional aspects will be set forth in the detailed description whichfollows, and, in part, will be apparent from the disclosure, or may belearned by practice of the inventive concepts.

According to one aspect of the invention, a display device includes: asubstrate including a first area having a first light transmittance anda second area adjacent to the first area having a second lighttransmittance; a plurality of pixels disposed on a first surface of thesubstrate; and a fingerprint sensor disposed in the first area on asecond surface of the substrate. The first light transmittance isgreater than the second light transmittance.

The plurality of pixels may include at least one first pixel in thefirst area and a second pixel in the second area.

The first pixel may include a light emitting area in which an image isdisplayed and a light transmission area in which a light is transmittedtherethrough.

The first pixel may include at least one first sub-pixel disposed in thelight emitting area. The first sub-pixel may include a first electrodedisposed on the substrate; an emission layer disposed on the firstelectrode; and a second electrode disposed on the emission layer.

The display device may further include an insulating layer disposedbetween the substrate and the first electrode, wherein the insulatinglayer extends into the transmission area. The display device may furtherinclude at least one of a pixel defining layer and passivation layerdisposed above the substrate, and wherein the insulating layer extendsinto at least one of the pixel defining layer and the passivation layer.In an exemplary embodiment, the first electrode and the second electrodemay extend across the transmission area.

The first sub-pixel may further include at least one structure selectedfrom the group of a hole injection layer, a hole transport layer, anelectron transport layer, and an electron injection layer, the at leastone structure being disposed between the first electrode and the secondelectrode, and wherein the at least one structured may extend across thetransmission area.

The second pixel may include at least one second sub-pixel, and a sizeof the first sub-pixel is smaller than a size of the second sub-pixel.According to an exemplary embodiment, each of the first sub-pixel andthe second sub-pixel may emit one wavelength of light selected from thegroup of red light, green light, and blue light.

The size of the first pixel may be the same as the size of the secondpixel, and the fingerprint sensor may be a photo sensor or an ultrasonicsensor.

The display device may further include a first sensor disposed on thesubstrate to sense a touch position input by a user. Further, the firstsensor may be a touch sensor of a self-capacitance type or a touchsensor of a mutual-capacitance type. The first sensor may include afirst touch electrode; and a second touch electrode spaced apart fromthe first touch electrode and forming a capacitance with the first touchelectrode.

The first touch electrode may have a mesh structure. The first touchelectrode may include a conductive polymer.

The display device may further include a second sensor disposed on thefirst surface of the substrate spaced apart from the first sensor andsensing a touch pressure.

The second sensor may include a conductive polymer.

The first sensor may have a hole in the first area and touch electrodesof the first sensor may be disposed in the second area. Touch electrodesof the second sensor may include a portion in the first area and aportion in the second area.

A sensing type of the first sensor may be different from a sensing typeof the second sensor.

At least a portion of the display device may be flexible and be bendableor rollable.

The light transmission area may be free of any light emittingcomponents.

The first surface may include a front surface of the substrate and thesecond surface comprises a rear surface of the substrate.

According to another aspect of the invention, a display device includes:a substrate including a first area having a first light transmittanceand a second area adjacent to the first area having a second lighttransmittance; a plurality of pixels disposed on a first surface of thesubstrate; and a first sensor disposed on the first surface of thesubstrate to sense a touch position; a second sensor disposed on thefirst surface of the substrate spaced apart from the first sensor tosense pressure applied by touch from a user; and a fingerprint sensordisposed in the first area on a second surface of the substrate. Thefirst area includes a light emitting area configured to display an imageand a light transmission area configured to transmit light.

The transmission area may be free of any light emitting components.

According to still another aspect of the invention, a display deviceincludes: a substrate including, in a plan view, a first area and asecond area; a first sub-pixel disposed on the substrate, the firstsub-pixel including an emission area disposed in the first area; asecond sub-pixel disposed on the substrate, the second sub-pixelincluding an emission area disposed in the second area; a transmissionarea disposed on the substrate, the transmission area being adjacent tothe second sub-pixel disposed in the second area; and a sensor disposedunder the substrate, the photo sensor disposed in the second area. Theemission area of the first sub-pixel has a first size and the emissionarea of the second sub-pixel has a second size different from the firstsize.

The sensor may be a fingerprint sensor.

The fingerprint sensor may be a photo sensor or an ultrasonic sensor.

The display device may further include: an insulating layer on thesubstrate. The transmission area may be formed by removing at least aportion of the insulating layer.

The second sub-pixel may include: a first electrode disposed on thesubstrate; an organic layer disposed on the first electrode; and asecond electrode disposed on the emission layer. The second electrodemay extend from the emission area of the second sub-pixel toward thetransmission area, and the transmission area may include an openingformed by the second electrode of the second sub-pixel.

The display device may further include: a third sub-pixel disposed onthe substrate, the third sub-pixel including an emission area disposedin the second area. Each of the second sub-pixel and the third sub-pixelmay include: a first electrode disposed on the substrate; an emissionlayer disposed on the first electrode; and a second electrode disposedon the emission layer. The second electrode of the second sub-pixel andthe second electrode of the third sub-pixel may be connected, and thetransmission area may include an opening formed by the second electrodeof the second sub-pixel and the second electrode the third sub-pixel.

The second sub-pixel may include: a first electrode disposed on thesubstrate; an organic layer disposed on the first electrode; and asecond electrode disposed on the emission layer. The organic layer maynot overlap the transmission area in the plan view.

At least one of the first electrode and the second electrode may extendinto the transmission area and overlap the transmission area in the planview.

The display device may further include: a touch sensor disposed on thesubstrate, the touch sensor comprising sensing electrodes. The sensingelectrodes may not overlap the transmission area in the plan view.

The first size may be larger than the second size.

According to still another aspect of the invention, a display deviceincludes: a substrate including, in a plan view, a first area and asecond area; a first sub-pixel disposed on the substrate, the firstsub-pixel including an emission area disposed in the first area; asecond sub-pixel disposed on the substrate, the second sub-pixelincluding an emission area disposed in the second area; a transmissionarea disposed on the substrate, the transmission area being adjacent tothe second sub-pixel disposed in the second area; and a touch sensordisposed on the substrate, the touch sensor comprising sensingelectrodes. At least a portion of the second area comprises an areawhere the sensing electrodes and the transmission area may be notoverlapped in the plan view.

The sensing electrodes may be not disposed in the second area.

The sensor may be a fingerprint sensor.

The fingerprint sensor may be a photo sensor or an ultrasonic sensor.

Accordingly, display devices constructed according to the principles ofthe invention provide an enhanced security function by including animproved fingerprint sensor.

Further, exemplary embodiments of the invention provide a high-qualitydisplay device in which resolution of an area including the fingerprintsensor is substantially the same as resolution of an area not includingthe fingerprint sensor.

In addition, exemplary embodiments of the invention provide a displaydevice which is capable of sensing a touch position and a touch pressurewhile sensing the fingerprint thereby enhancing convenience of use.

The foregoing general description and the following detailed descriptionare exemplary and explanatory and are intended to provide furtherexplanation of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the inventive concepts, and are incorporated in andconstitute a part of this specification, illustrate exemplaryembodiments of the inventive concepts, and, together with thedescription, serve to explain principles of the inventive concepts.

FIG. 1A is a plan view of a display device constructed according to theprinciples of the invention.

FIG. 1B is a cross-sectional view taken along a line I-I′ of FIG. 1A.

FIG. 2 is a block diagram graphically illustrating some of thecomponents of an exemplary display device according to exemplaryembodiments.

FIG. 3 is a plan view illustrating an exemplary display panelconstructed according to the principles of the invention.

FIG. 4A is a plan view illustrating a first pixel of FIG. 3 rotated by90 degrees from the position shown in FIG. 3.

FIG. 4B is a cross-sectional view of a first embodiment of the firstpixel taken along a line II-II′ of FIG. 4A.

FIG. 4C is a cross-sectional view of a second embodiment of the firstpixel taken along a line II-II′ of FIG. 4A.

FIG. 5A is a plan view illustrating a second pixel in FIG. 3 rotated by90 degree s from the position shown in FIG. 3, and FIG. 5B is across-sectional view taken along a line III-III′ of FIG. 5A.

FIG. 6 is a cross-sectional view of an exemplary display device takenalong a line corresponding to a line I-I′ of FIG. 1.

FIG. 7 is a block diagram graphically illustrating some of thecomponents of an exemplary display device according to exemplaryembodiments.

FIG. 8A illustrates an exemplary first sensor of a self-capacitance typethat may be used in display devices of the invention.

FIG. 8B illustrates an exemplary first sensor of a mutual-capacitancetype that may be used in display devices of the invention.

FIG. 9 is a cross-sectional view of another exemplary display devicetaken along a line corresponding to a line I-I′ of FIG. 1.

FIG. 10 is a block diagram graphically illustrating some of thecomponents of an exemplary display device according to exemplaryembodiments.

FIGS. 11A to 11C are plan views illustrating a second sensor accordingto exemplary embodiments.

FIG. 12 is a cross-sectional view of another exemplary display devicetaken along a line corresponding to a line I-I′ of FIG. 1.

FIG. 13 is a plan view illustrating a first sensor in the display deviceof FIG. 12.

FIG. 14 is a perspective view illustrating a display device constructedaccording to the principles of the invention.

FIG. 15A is a cross-sectional view illustrating the display device ofFIG. 14 in a folded position.

FIG. 15B is a cross-sectional view illustrating the display device ofFIG. 14 in a rolled position.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

In the following description, for the purposes of explanation, numerousspecific details are set forth in order to provide a thoroughunderstanding of various exemplary embodiments. It is apparent, however,that various exemplary embodiments may be practiced without thesespecific details or with one or more equivalent arrangements. In otherinstances, well-known structures and devices are shown in block diagramform in order to avoid unnecessarily obscuring various exemplaryembodiments.

In the accompanying figures, the size and relative sizes of layers,films, panels, regions, etc., may be exaggerated for clarity anddescriptive purposes. Also, like reference numerals denote likeelements.

When an element or layer is referred to as being “on,” “connected to,”or “coupled to” another element or layer, it may be directly on,connected to, or coupled to the other element or layer or interveningelements or layers may be present. When, however, an element or layer isreferred to as being “directly on,” “directly connected to,” or“directly coupled to” another element or layer, there are no interveningelements or layers present. For the purposes of this disclosure, “atleast one of X, Y, and Z” and “at least one selected from the groupconsisting of X, Y, and Z” may be construed as X only, Y only, Z only,or any combination of two or more of X, Y, and Z, such as, for instance,XYZ, XYY, YZ, and ZZ. Like numbers refer to like elements throughout. Asused herein, the term “and/or” includes any and all combinations of oneor more of the associated listed items.

Although the terms first, second, etc. may be used herein to describevarious elements, components, regions, layers, and/or sections, theseelements, components, regions, layers, and/or sections should not belimited by these terms. These terms are used to distinguish one element,component, region, layer, and/or section from another element,component, region, layer, and/or section. Thus, a first element,component, region, layer, and/or section discussed below could be termeda second element, component, region, layer, and/or section withoutdeparting from the teachings of the disclosure.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper,” and the like, may be used herein for descriptive purposes, and,thereby, to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the drawings. Spatiallyrelative terms are intended to encompass different orientations of anapparatus in use, operation, and/or manufacture in addition to theorientation depicted in the drawings. For example, if the apparatus inthe drawings is turned over, elements described as “below” or “beneath”other elements or features would then be oriented “above” the otherelements or features. Thus, the exemplary term “below” can encompassboth an orientation of above and below. Furthermore, the apparatus maybe otherwise oriented (e.g., rotated 90 degrees or at otherorientations), and, as such, the spatially relative descriptors usedherein interpreted accordingly.

The terminology used herein is for the purpose of describing particularembodiments and is not intended to be limiting. As used herein, thesingular forms, “a,” “an,” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. Moreover,the terms “comprises,” “comprising,” “includes,” and/or “including,”when used in this specification, specify the presence of statedfeatures, integers, steps, operations, elements, components, and/orgroups thereof, but do not preclude the presence or addition of one ormore other features, integers, steps, operations, elements, components,and/or groups thereof.

Various exemplary embodiments are described herein with reference tosectional illustrations that are schematic illustrations of idealizedexemplary embodiments and/or intermediate structures. As such,variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected. Thus, exemplary embodiments disclosed herein should not beconstrued as limited to the particular illustrated shapes of regions,but are to include deviations in shapes that result from, for instance,manufacturing. For example, an implanted region illustrated as arectangle will, typically, have rounded or curved features and/or agradient of implant concentration at its edges rather than a binarychange from implanted to non-implanted region. Likewise, a buried regionformed by implantation may result in some implantation in the regionbetween the buried region and the surface through which the implantationtakes place. Thus, the regions illustrated in the drawings are schematicin nature and their shapes are not intended to illustrate the actualshape of a region of a device and are not intended to be limiting.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure is a part. Terms,such as those defined in commonly used dictionaries, should beinterpreted as having a meaning that is consistent with their meaning inthe context of the relevant art and will not be interpreted in anidealized or overly formal sense, unless expressly so defined herein.

FIG. 1A is a plan view of a display device constructed according to theprinciples of the invention, and FIG. 1B is a cross-sectional view takenalong a line I-I′ of FIG. 1A. FIG. 2 is a block diagram graphicallyillustrating some of the components of an exemplary display deviceaccording to exemplary embodiments.

Referring to FIGS. 1A, 1B and 2, an exemplary display device DP includesa display panel PNL and a window WD disposed on a front surface of adisplay panel PNL.

The display panel PNL displays arbitrary visual information, for examplea text, a video, a photo, 2 dimension or 3 dimension image, etc. to thefront surface. The type of the display panel PNL that displays the imageis not particularly important and the invention is not limited to aspecific type of display device.

Thus, in an exemplary embodiment, the display panel PNL is described asan organic light emitting display panel as an example. However, the kindof the display panel PNL is not limited thereto, and other displaypanels PNL may be used in a scope of the invention.

The display panel PNL may be provided various shapes, for example arectangular-plate shape having two pairs of sides parallel with eachother. In the case where the display panel PNL is provided as therectangular-plate shape, one pair of sides selected from two pairs ofsides may be longer than the other pair of sides. In an exemplaryembodiment, the shape of the display panel PNL is described as arectangular shape having a pair of long sides and a pair of short sidesfor convenience of description.

However, the shape of the display panel PNL is not limited thereto, andthe display panel PNL may have various shapes. For example, the displaypanel PNL may have various shapes such as an closed polygon including aside made of a straight line, a circle, an ellipse, and the likeincluding a side made of a curved line, and a semicircle, asemi-ellipse, and the like including a side made of a straight line anda curved line. In an exemplary embodiment, when the display panel PNLhas sides made of a straight line, at least a portion of edges of eachshape may be made of the curved line. For example, when the displaypanel PNL has a rectangular shape, a portion, at which adjacent straightlines meet each other, may be replaced with a curved line having apredetermined curvature. That is, an apex of a rectangular shape may bemade of a curved side of which opposite side adjacent to each other isconnected to two straight sides and which has a predetermined curvature.

The curvature may be varied according to position. For example, thecurvature may be varied according to a starting position of the curvedline, a length of the curved line, etc.

An entire portion or at least one portion of the display panel PNL mayhave flexibility as is known in the art. For example, the display panelPNL may have flexibility in an entire area, or may have flexibility inone area corresponding to a flexible area.

The display panel PNL may display an image on a front surface. Thedisplay panel PNL includes a display area DA displaying an image via adisplay unit PP and a non-display area NDA disposed at least one side ofthe display area DA. For example, the non-display area NDA may enclosethe display area DA.

The shape of the display area DA may correspond to the shape of thedisplay device DP. For example, like the shape of the display device DP,the display area DA may have various shapes such as a closed polygonincluding a side made of a straight line, a circle, an ellipse, and thelike including a side made of a curved line, and a semicircle, asemi-ellipse, and the like including a side made of a straight line anda curved line. In exemplary embodiments, the display area DA may have arectangular shape.

The display panel PNL includes a first area A1 for sensing thefingerprint and a second area A2 adjacent to the first area A1. Inexemplary embodiments, the size of the first area A1 may be smaller thanthe size of the second area A2. The first area A1 may have a size and ashape which are capable of sensing a fingerprint of a user with meansknown in the art. In exemplary embodiments, the first area A1 is shownand described as a rectangular shape for convenience of description, butis not limited thereto, and could have other shapes, such as a circle,an ellipse, a semicircle, a polygon, etc. The first area A1 may beenclosed by the second area A2, but is not limited thereto. In exemplaryembodiments, the first area A1 may be only disposed at one side of thesecond area A2. The first area A1 may be disposed in the display areaDA. The second area A2 may be disposed in the display area DA and thenon-display area NDA. However, the position of the first area A1 and thesecond area A2 are not limited thereto, and the first area A1 and thesecond area A2 may be disposed in various positions. For example, aportion of the first area A1 may be disposed in the non-display areaNDA. Alternatively, both first area A1 and second area A2 may bedisposed only in the display area DA.

In exemplary embodiments, in order to sense the fingerprint through thefirst area A1, the first area transmits more light therethrough than thesecond area. In exemplary embodiments, as the light transmittance of thefirst area A1 is higher than the light transmittance of the second area,the sensing power and sensitivity of the fingerprint sensor, describedbelow, may be improved.

A window WD is disposed on a front surface of the display panel PNL. Thewindow WD has a plate-like shape corresponding to the shape of thedisplay panel PNL and covers at least one portion of the front surfaceof the display panel PNL. For example, when the display panel PNL has arectangular shape, the window WD has also a rectangular shapecorresponding to the display panel PNL. In addition, when the displaypanel PNL has a circle shape, the window WD has also a circle shapecorresponding to the display panel PNL.

The window WD transmits an image emitted from the display panel PNL andsimultaneously protects against impact from the outside, therebypreventing the display panel PNL from being damaged or malfunction. Term“the impact from the outside” means external power such as a pressure, astress, or the like, that may cause defects in the display panel PNL.

An entire portion or at least one portion of the window WD may haveflexibility. For example, the window WD may have flexibility in anentire area, or may have flexibility in one area corresponding to aflexible area.

In detail, the display panel PNL includes a substrate SUB, a displayunit PP disposed on a front surface of the substrate SUB, and afingerprint sensor FPS disposed on a rear surface of the substrate SUB.

The substrate SUB may be made of an insulating material such as aquartz, a synthetic quartz, a calcium fluoride, a fluorine-doped quartz,a soda-lime glass, a non-alkali glass, a resin, etc. In addition, thesubstrate SUB may be made of a flexible material so as to be bendable orfoldable, and may have a single-layer structure or a multi-layerstructure.

For example, the substrate SUB may include at least one materialselected from polystyrene, polyvinyl alcohol, polymethylmethacrylate,polyethersulfone, polyacrylate, polyetherimide, polyethylenenaphthalate, polyethylene terephthalate, polyphenylene sulfide,polyarylate, polyimide, polycarbonate, triacetate cellulose, andcellulose acetate propionate. However, the material forming thesubstrate SUB may be variously changed, and the substrate SUB may bemade of a glass fiber reinforced plastics (GFRP), or other materialsknown in the art.

In exemplary embodiments, the substrate SUB may be a polyimidesubstrate. The polyimide substrate may be made of a first polyimidelayer, a barrier film layer, a second polyimide layer, etc. When thepolyimide substrate is thin and flexible, the polyimide substrate may beformed on a hard carrier substrate to support a light emittingstructure.

That is, in exemplary embodiments, the substrate SUB may have astructure in which the first polyimide layer, the barrier film layer,and the second polyimide layer are stacked on the carrier substrate. Forexample, after an insulating layer is formed on the second polyimide, athin film transistor, a light emitting element, and the like may beformed on the insulating layer.

After forming this light emitting structure, the carrier substrate maybe removed. Since the polyimide substrate is thin and flexible, thelight emitting structure may be difficult to be formed on the polyimidesubstrate. Considering this, after forming the light emitting structureby using a rigid carrier substrate, the carrier substrate is removed,thereby using the polyimide substrate as the substrate SUB.

The substrate SUB has a front surface and a rear surface opposite to thefront surface.

Since the substrate SUB is a portion of the display panel PNL, each ofareas of the substrate SUB is described as corresponding to each of thedisplay area DA, the non-display area NDA, the first area A1, and thesecond area A2 refers the display area DA, the non-display area NDA, thefirst area A1, and the second area A2 for convenience of description.

The display unit PP may be disposed on the front surface of thesubstrate SUB. In exemplary embodiments, the display unit PP may bedisposed in the display area DA except the non-display area NDA. Thedisplay unit PP is disposed in each of the first area A1 and the secondarea A2.

The display unit PP displays information input by a user or informationproviding to the user as an image as known in the art. In other words,the display unit PP displays data input by a user and the result of anoperation performed by the user and/or a reaction according to the inputdata. The display unit PP will be described later.

The fingerprint sensor FPS is disposed on the rear surface of thesubstrate SUB, and may be any number of known elements for sensing thefingerprint of the user, as discussed below. The fingerprint sensor FPSis only disposed in the first area A1 of the rear surface of thesubstrate SUB and is not disposed in the second area A2. The fingerprintsensor FPS may be connected to a sensor control unit SC through aseparate wire, a flexible printed circuit substrate, a tape carrierpackage, a connector, a chip on film, or other means known in the art.The fingerprint sensor FPS may be a photo sensor or an ultrasonicsensor. The fingerprint sensor according to exemplary embodiments may bea photo sensor, and the photo sensor may recognize a fingerprint bydistinguishing a wavelength of reflected light changed according to aridge or a valley of the fingerprint which contacts the display panelPNL of the display device DP. The fingerprint sensor FPS may recognizethe fingerprint not only when a finger of the user is in contacttherewith, but also when the finger moves into a state of being incontact therewith. However, the fingerprint sensor FPS according toexemplary embodiments is not limited thereto, and may include varioustypes. For example, the fingerprint sensor may be a capacitive type, aheat sensing type, a non-contact type, or other types of fingerprintsensors known in the art.

Referring to FIG. 2, the display device DP according to exemplaryembodiments may further include a sensor control unit SC and a displaydriving unit PC.

The sensor control unit SC may control an operation of the fingerprintsensor FPS, and may sense a variation of light in the fingerprint sensorFPS, thereby sensing the fingerprint of the user.

The display driving unit PC provides an image driving signal to thedisplay panel PNL, thereby controlling an image display operation of thedisplay panel PNL. For this purpose, the display driving unit PC maygenerate the image driving signal by using an image data and a controlsignal provided from the outside. For example, the display driving unitPC may be provided the image data and the control signal from a host(not shown), and the control signal may have a vertical synchronizationsignal, a horizontal synchronization signal, a main clock signal, andthe like. In addition, the image driving signal may include a scansignal and a data signal generated by using the image data.

The sensor control unit SC and the display driving unit PC may beintegrated into a single configuration. For example, the sensor controlunit SC and the display driving unit PC may be disposed in a single IC(integrated circuit).

FIG. 3 is a plan view illustrating an exemplary a display panelconstructed according to the principles of the invention. Specifically,FIG. 3 shows a display unit PP (referring to FIG. 1B) of a display panelPNL.

Referring to FIG. 3, the display unit PP includes a first area A1 forsensing the fingerprint and the second area A2 adjacent to the firstarea A1. The first pixel PX1 is disposed in the first area A1, and thesecond pixel PX2 is disposed in the second area A2.

In exemplary embodiments, the size of the first pixel PX1 in the firstarea A1 may be substantially the same as the size of the second pixelPX2 in the second area A2. Therefore, the number of first pixels PX1 perunit area in the first area A1 may be substantially the same as thenumber of second pixels PX2 per unit area in the second area A2.Accordingly, the resolution of an area (i.e., the first area A1) inwhich the fingerprint sensor is disposed may be substantially the sameas the resolution of an area (i.e., the second area A2) in which thefingerprint sensor is not disposed.

FIG. 4A is a plan view illustrating a first pixel of FIG. 3 rotated by90 degrees from the position shown in FIG. 3, and FIG. 4B is across-sectional view of a first embodiment of the first pixel takenalong a line of FIG. 4A.

First, referring to FIG. 3, in the display device DP according toexemplary embodiments, the display unit PP includes a plurality ofpixels disposed in the display area DA. The plurality of pixels may bearranged as a matrix form having a row and a column. However, the pixelsmay be arranged in a different form from the matrix form, and inexemplary embodiments, pixels being arranged in regular rows and thecolumns are illustrated as an example for convenience of description.

The pixels according to exemplary embodiments include at least one firstpixel PX1 disposed in the first area A1 and at least one second pixelPX2 disposed in the second area A2. Each of the first pixel PX1 and thesecond pixel PX2 may be in plural. The number of the pixels according toexemplary embodiments is set for convenience of description, the firstpixel PX1 of a number more than an illustrated number may be provided inthe first area A1, and the second pixel PX2 of a number more than anillustrated number may be provided in the second area A2.

Next, referring to FIGS. 4A and 4B, the first pixels PX1 are disposed inthe first area A1. Each of the first pixels PX1 includes at least onefirst sub-pixel. In exemplary embodiments, the first pixel PX1 mayinclude three first sub-pixels SP1, SP2, and SP3. However, the number ofsub-pixels of the first pixel PX1 is not limited thereto. Three firstsub-pixels SP1, SP2, and SP3 may be a blue sub-pixel, a green sub-pixel,and a red sub-pixel emitting respectively blue light, green light, andred light. However, the color of each of the first sub-pixels is notlimited thereto, and the color of each of the first sub-pixels may be acolor different from the color as described above, for example, magentalight, yellow light, cyan light, white light, or the like.

The first area A1 has a light emitting area EA in which light is emittedand a transmission area in which light is transmitted only and notemitted. The light emitting area EA and the transmission area TA may bedisposed in each of the first pixels PX1, and one transmission area TAand three light emitting areas EA are shown and described as beingdisposed in each of the first pixels PX1 in FIGS. 4A and 4B for ease ofillustration.

In exemplary embodiments, three light emitting areas EA are sequentiallyarranged in one direction (e.g., a horizontal direction in the drawing).The transmission area TA extends in one direction, e.g., horizontal asin the drawing. The light emitting area EA and the transmission area TAmay have various shapes and numbers. For example, the light emittingarea EA and the transmission area TA may be arranged in other directions(e.g., a vertical direction) different from one direction illustrated.In exemplary embodiments, the transmission area TA are also provided inplural, for example, three, and a plurality of transmission areas TA maybe also disposed in one direction. Alternatively, the transmission areaTA and the light emitting area EA may be alternately disposed in onedirection. In exemplary embodiments, each of the transmission area TAand the light emitting area EA is illustrated as a quadrangle, but isnot limited thereto, and may have various shapes such as a polygon, acircle, or the like.

The first sub-pixels may be disposed in each of the light emitting areaEA. In other words, the first sub-pixels SP1, SP2, and SP3 may bedisposed in the light emitting area EA except the transmission area TA.

The transmission area TA may have opening OPN so that light passesthrough the transmission area TA, and light is not emitted since thefirst sub-pixels are not disposed therein. The transmission area TAforms a path through which light or an ultrasonic wave moves to thefingerprint sensor FPS without interference from emitted light from apixel.

Referring to FIG. 4B, the first pixel PX1 will be described belowaccording to a stacking order.

The first sub-pixel is disposed in the light emitting area EA of thefirst pixel PX1.

The first sub-pixel according to exemplary embodiments may include aninsulating layer, a pixel definition layer PDL, a thin film transistorTFT, a light emitting element, and a cover layer CV disposed on thesubstrate SUB. Herein, a thin film transistor TFT may include an activepattern ACT, a gate electrode GE, a source electrode SE, and a drainelectrode DE. The insulating layer may include a buffer layer BF, a gateinsulating layer GI, an interlayer insulating layer IL, and apassivation layer PSV. The light emitting element may include a firstelectrode EL1, a second electrode EL2, and an organic layer disposedbetween the first electrode EL1 and the second electrode EL2.

The buffer layer BF is disposed on the substrate SUB.

The buffer layer BF may prevent metal atoms or impurities from spreadingfrom the substrate SUB, and during a crystallization process for formingthe active pattern ACT, may control the speed of heat transfer, therebyobtaining a substantially uniform active pattern ACT. In addition, inthe case where a surface of the substrate SUB is not uniform, the bufferlayer BF may improve flatness of the surface of the substrate SUB.According to the type of the substrate SUB, two or more buffer layers BFmay be provided, or the buffer layer BF may be not provided on thesubstrate SUB.

The active pattern ACT is disposed on the buffer layer BF. The activepattern ACT may include an oxide semiconductor, an inorganicsemiconductor (i.e., amorphous silicon, poly silicon), an organicsemiconductor, or the like.

The gate insulating layer GI may be disposed on the active pattern ACT.The gate insulating layer GI covers the active pattern ACT. The gateinsulating layer GI may be entirely disposed on the substrate SUB. Thegate insulating layer GI may be made of various insulating materialsknown in the art, such as a silicon oxide, a silicon nitride, a metaloxide, or the like.

The gate electrode GE may be disposed on a portion of the gateinsulating layer GI corresponding to the active pattern ACT disposedtherebelow. The gate electrode GE may be made of a metal, an alloy, ametal nitride, a conductive metal oxide, a transparent conductivematerial, or the like.

The interlayer insulating layer IL may be disposed on the gate electrodeGE. The interlayer insulating layer IL may cover the gate electrode GEin the light emitting area EA, and may extend in one direction of thesubstrate SUB. That is, the interlayer insulating layer IL may beentirely disposed on the substrate SUB. The interlayer insulating layerIL may include a silicon compound, a metal oxide, or the like.

The source electrode SE and the drain electrode DE may be disposed onthe interlayer insulating layer IL. The source electrode SE and thedrain electrode DE may pass through a portion of both the gateinsulating layer GI and the interlayer insulating layer IL, therebybeing respectively connected to one side and other side of the activepattern ACT. Each of the source electrode SE and the drain electrode DEmay include a metal, an alloy, a metal nitride, a conductive metaloxide, a transparent conductive material, or the like.

The passivation layer PSV may be disposed on the source electrode SE andthe drain electrode DE. The passivation layer PSV may cover the sourceelectrode SE and the drain electrode DE in the light emitting area EA,and may extend in one direction on the substrate SUB. That is, thepassivation layer PSV may be entirely disposed on the substrate SUB. Thepassivation layer PSV may include a silicon compound, a metal oxide, orthe like.

The first electrode EL1 may be disposed on the passivation layer PSV.The first electrode EL1 may pass through a portion of the passivationlayer PSV, thereby being connected to the drain electrode DE. The firstelectrode EL1 may include a metal, an alloy, a metal nitride, aconductive metal oxide, a transparent conductive material, or the like.

The pixel definition layer PDL may be disposed on the passivation layerPSV while exposing a portion of the first electrode EL1. The pixeldefinition layer PDL may be made of an organic material or an inorganicmaterial. In this case, the organic layer may be disposed on the firstelectrode EL1 of which at least a portion is exposed by the pixeldefinition layer PDL.

The organic layer may include a hole injection layer HIL, a holetransport layer HTL, an emission layer EML, an electron transport layerETL, and an electron injection layer EIL. Like this exemplaryembodiment, the hole injection layer HIL, the hole transport layer HTL,the electron transport layer ETL, and electron injection layer EIL allmay be formed, but in other embodiments one or two layers thereof may beomitted. The emission layer may emit light of various colors based onthe type of sub-pixel. The emission layer may emit for example, at leastone wavelength selected from red light, blue light, and red light, butembodiments are not limited thereto. The emission layer may emit othercolor light.

The second electrode EL2 may be disposed on the pixel definition layerPDL and the organic layer. The second electrode EL2 may cover the pixeldefinition layer PDL and the organic layer, and may extend in onedirection on the substrate SUB. The second electrode EL2 may be made ofa metal, an alloy, a metal nitride, a conductive metal oxide, atransparent conductive material, or other materials known in the art.These may be used alone or in combination with each other.

The cover layer CV is disposed on the second electrode EL2.

The cover layer CV may be made of a single layer or a multi-layer. Inexemplary embodiments, the cover layer CV may be made of a triple-layer.The cover layer CV may be made of an organic material and/or aninorganic material. The cover layer CV disposed at the outermost may bemade of an inorganic material. In exemplary embodiments, the cover layerCV may be made of an inorganic material/an organic material/an inorganicmaterial, but is not limited thereto. The organic material may includean organic insulating material such as a polyacryl compound, a polyimidecompound, a fluorine carbon compound like a teflon, a benzocyclobutenecompound, or the like, and the inorganic material may include apolysiloxane, a silicon nitride, a silicon oxide, silicon oxynitride, orthe like.

Although not shown, an encapsulation layer may be further disposed onthe cover layer CV. The encapsulation layer may be provided as aplate-shaped glass or a polymer film. The encapsulation layer mayprotect elements between the substrate SUB and the encapsulation layerfrom the outside.

The opening OPN is disposed in the transmission area TA of the firstpixel PX1. The opening OPN may be formed by removing at least a portionof the insulating layer and elements for emitting light. For example,the opening OPN may be formed by the interlayer insulating layer IL, thepassivation layer PSV, the pixel definition layer PDL, second electrodeEL2, or the like. However, the elements removed from the opening OPN arenot limited thereto, for example, the gate insulating layer GI or thebuffer layer BF may be removed.

By forming the opening OPN in the transmission area TA of the firstpixel PX1 in the first area A1, light passing through the opening OPNfrom an upper side to a lower side (e.g. ambient light) may directlyreach the fingerprint sensor FPS in the first area A1, or light may passthrough the opening OPN from the fingerprint sensor FPS to the upperside (provided that the fingerprint sensor FPS can emit light.

In exemplary embodiments, the transmission area TA may have a differentshape from a shape described above.

FIG. 4C is a cross-sectional view of a second embodiment of the firstpixel PX1 taken along a line II-II′ of FIG. 4A. Hereinafter, in order toavoid repetitive description, only the differences from the first,exemplary embodiment described above will be mainly described. Inaddition, it an element that functions substantially identically with apreviously described element will be indicated by the same referencenumber.

Referring to FIGS. 4A and 4C, the first sub-pixel is disposed in thelight emitting area EA of the first pixel PX1.

The first sub-pixel according to exemplary embodiments may include aninsulating layer, a pixel definition layer PDL, a thin film transistorTFT, a light emitting element, and a cover layer CV disposed on thelight emitting area EA in the substrate SUB. Herein, a thin filmtransistor TFT may include an active pattern ACT, a gate electrode GE, asource electrode SE, and a drain electrode DE. The insulating layer mayinclude a buffer layer BF, a gate insulating layer GI, an interlayerinsulating layer IL, and a passivation layer PSV. The light emittingelement may include a first electrode EL1, a second electrode EL2, andan organic layer disposed between the first electrode EL1 and the secondelectrode EL2.

The insulating layer and the first electrode EL1 may be disposed ontransmission area TA in the substrate SUB. More particularly, the bufferlayer BF, the gate insulating layer GI, the interlayer insulating layerIL, the passivation layer PSV, and the first electrode EL1 may besequentially stacked.

Each of the buffer layer BF, the gate insulating layer GI, theinterlayer insulating layer IL, the passivation layer PSV, and firstelectrode EL1 may have a shape extending from the light emitting areaEA.

In the pixel definition layer PDL, an opening is formed so that thefirst electrode EL1 corresponding to the light emitting area EA isexposed. Further, in the pixel definition layer PDL, an opening isformed so that the first electrode EL1 corresponding to the transmissionarea TA is exposed. A portion of the organic layer except for theemission layer EML may be sequentially disposed on the first electrodeEL1 exposed in the transmission area TA. That is, at least one layerselected from the hole injection layer HIL, a hole transport layer HTL,an electron transport layer ETL, and an electron injection layer EIL maybe disposed on the first electrode EL1 in the transmission area TA.

Since the organic layer does not include the emission layer EML emittinga light, the organic layer is entirely transparent. Therefore, light maypass through the organic layer.

Elements of each of the light emitting area EA and the transmission areaTA may be formed by or in the same process. For example, in the case offorming the organic layer, the hole injection layer HIL except for theemission layer EML, the hole transport layer HTL, the electron transportlayer ETL, and the electron injection layer EIL may be simultaneouslyformed in the light emitting area EA and the transmission area TA, andthe emission layer EML may be only formed in the light emitting area EA.

FIG. 5A is a plan view illustrating a second pixel PX2 of FIG. 3 rotatedby 90 degrees from the position shown in FIG. 3, and FIG. 5B is across-sectional view taken along a line of FIG. 5A.

Referring to FIGS. 5A and 5B, in the second pixel PX2, the lightemitting area EA is provided, but the transmission area TA is notprovided. The light emitting area EA may be provided in each of secondpixels PX2, and three light emitting areas EA may be provided in onepixel in FIG. 5A.

In exemplary embodiments, three light emitting areas EA may besequentially arranged in one direction (e.g., a horizontal direction ina drawing). However, the light emitting area EA may be disposed withvarious shapes and numbers. For example, the light emitting area EA maybe arranged in other direction (e.g., a vertical direction) differentfrom one direction illustrated. In exemplary embodiments, the lightemitting area EA is illustrated as a quadrangle, but is not limitedthereto, and may have various shapes such as a polygon, a circle, or thelike.

Referring to FIG. 5A again, three second sub-pixels SP1′, SP2′, and SP3′may be provided in the light emitting area EA. The second sub-pixels maybe provided in each of the light emitting area EA.

The second sub-pixel according to exemplary embodiments may include abuffer layer BF, a gate insulating layer GI, an interlayer insulatinglayer IL, a passivation layer PSV, a pixel definition layer PDL, a thinfilm transistor TFT, a light emitting element, and a cover layer CVdisposed on the substrate SUB. Herein, a thin film transistor TFT mayinclude an active pattern ACT, a gate electrode GE, a source electrodeSE, and a drain electrode DE. The light emitting element may include afirst electrode EL1, a second electrode EL2, and an organic layerdisposed between the first electrode EL1 and the second electrode EL2.The organic layer may include a hole injection layer HIL, a holetransport layer HTL, an emission layer EML, an electron transport layerETL, and an electron injection layer EIL.

The second sub-pixel has substantially the same structure as the firstsub-pixel as shown in FIG. 4C except for the pixel definition layer PDLand the light emitting element. However, the second sub-pixel does nothave a portion corresponding to the transmission area (TA; referring toFIG. 4C) unlike the first sub-pixel shown in FIG. 4C, and has a shape inwhich the light emitting area (EA; referring to FIG. 4C) extends. Thesize of the second sub-pixel may be larger than the size of the firstsub-pixel. Even though the size of the first pixel PX1 is substantiallythe same as the size of the second pixel PX2, since the transmissionarea TA is disposed in the first pixel PX1, the size of the lightemitting area EA of the first pixel PX1 is smaller than the size of thelight emitting area EA of the second pixel PX2. Accordingly, the size ofthe first sub-pixel disposed in the light emitting area EA of the firstpixel PX1 is smaller than the size of the second sub-pixel disposed inthe light emitting area EA of the second pixel PX2.

In the second sub-pixel, the pixel definition layer PDL is disposedalong an edge of the light emitting area EA, and the organic layer isdisposed in the pixel definition layer PDL.

In the display device DP having a structure described above, thetransmittance of light through the first area A1, in which thefingerprint sensor is disposed, is greater than the transmittance oflight through the second area A2, in which the fingerprint sensor FPS isnot disposed. Therefore, the fingerprint sensor FPS may easily sense afingerprint of a user.

In exemplary embodiments, the case where a difference in lighttransmittance is realized by allowing the size of the sub-pixels in thefirst area A1 to be less than the size of the sub-pixels in the secondarea A2, has been described, but embodiments of the invention are notlimited thereto. The difference in transmittance may be realized byother means known in the art, e.g., by modifying the wire structure,etc. in the first area A1 and the second area A2, in addition to orinstead of the method described above. For example, the difference intransmittance between the first area A1 and the second area A2 may berealized by relatively narrowly forming the width of a wire in the firstarea A1 and relatively widely forming the width of the wire in thesecond area A2.

In addition, in exemplary embodiments, it is described that by removinga portion of the insulating layer, the light transmittance of the firstarea A1 is improved, but the invention is not limited thereto, and thedifference of the transmittance may be realized other means known in theart, e.g., by controlling the thickness of each of the buffer layer BF,the gate insulating layer GI, the interlayer insulating layer IL, thepassivation layer PSV and/or the cover layer CV in the first area A1 andthe second area A2.

When there is a touch by a user in the first area A1, the display deviceDP having a structure described above may recognize a fingerprint of theuser by using the fingerprint sensor FPS disposed in the rear surface ofthe substrate SUB. For example, in the case where the fingerprint sensorFPS is a photo sensor, since light passes through the transmission areaTA of the first area A1, the fingerprint of the user may be sensed bysensing the light. In addition, in the case where the fingerprint sensorFPS is an ultrasonic sensor, since an ultrasonic wave passes through thetransmission area TA of the first area A1, the fingerprint of the usermay be sensed by sensing the ultrasonic wave.

The display device DP according to exemplary embodiments may furtherinclude other sensor elements to sense a touch position of a user inaddition to the elements described above.

FIG. 6 is a cross-sectional view of an exemplary display device DP takenalong a line corresponding to a line I-I′ of FIG. 1. FIG. 7 is a blockdiagram graphically illustrating some of the components of an exemplarydisplay device DP according to exemplary embodiments.

Referring to FIGS. 6 and 7, a display panel PNL of the display device DPaccording to exemplary embodiments includes a substrate SUB, a displayunit PP disposed on the substrate SUB, a first sensor S1 disposed on thedisplay unit PP, and the fingerprint sensor FPS disposed in a rearsurface of the substrate SUB.

Since the substrate SUB, the display unit PP, and the fingerprint sensorFPS may be substantially the same as the exemplary embodiments describedabove, a detailed description thereof is omitted, and only thedifference from the exemplary embodiments described above will be mainlydescribed.

The first sensor S1 is a sensor for sensing a touch position when a usertouches. The first sensor S1 may be a sensor of various types known inthe art, for example, a capacitive type, a resistive type, or the like.

In exemplary embodiments, a sensor control unit SC may control anoperation of the fingerprint sensor FPS and the first sensor S1. Thesensor control unit SC may sense a variation of light in the fingerprintsensor FPS, thereby sensing the fingerprint of the user, and may sensecapacitance, etc. of the first sensor S1, thereby sensing a touchposition according to a touch of the user. In exemplary embodiments, thesensor control unit SC may simultaneously drive the fingerprint sensorFPS and the first sensor S1, or sequentially drive these sensors.

In exemplary embodiments, the first sensor S1 is described as beingdisposed on the display unit PP, but the invention is not limitedthereto. The first sensor S1 may be disposed at other positions inaddition to an upper of the display unit PP. For example, the firstsensor may be disposed between the substrate SUB and the display unitPP, or may be disposed inside the display unit PP.

As shown in FIG. 6, in the case where the first sensor S1 is disposedinside the display panel PNL, the first sensor S1 may be integrated withthe display panel PNL. Accordingly, an undesirable substrate SUB orlayer may be removed, thereby reducing the thickness of the displaydevice DP and manufacturing costs.

FIG. 8A illustrates an exemplary first sensor of a self-capacitance typethat may be used in display devices of the invention, and FIG. 8Billustrates an exemplary first sensor of a mutual-capacitance type thatmay be used in display devices of the invention.

Referring to FIG. 8A, the first sensor S1 according to exemplaryembodiments may be a sensor of self-capacitance type.

The first sensor S1 according to exemplary embodiments may include aplurality of touch electrodes SS1, a plurality of wires TRL, and aplurality of pads TRP disposed in one ends of the wires TRL.

In exemplary embodiments, the touch electrodes SS1 are shown anddescribed as having a rectangular shape, but the invention is notlimited thereto. The touch electrodes SS1 may be varied into variousshapes. For example, each of the touch electrodes SS1 has a circleshape. In addition, each of the touch electrodes SS1 may extend in onedirection to be entirely a stripe shape.

In the case where the touch electrodes SS1 extends in the one direction,the extending direction may be variously changed into a long sidedirection of a substrate SUB, a short side direction thereof, a inclineddirection thereof, or the like.

The touch electrodes SS1 may include a conductive material. For example,the conductive material may include a metal, an alloy thereof, aconductive polymer, a conductive metal oxide, or the like. In exemplaryembodiments, the metal may include copper, silver, gold, platinum,palladium, nickel, tin, aluminum, cobalt, rhodium, iridium, iron,ruthenium, osmium, manganese, molybdenum, tungsten, niobium, tantalum,titanium, bismuth, antimony, lead, or the like. The conductive metaloxide may include indium tin oxide (ITO), indium zinc oxide (IZO),antimony zinc oxide (AZO), indium tin zinc oxide (ITZO), zinc oxide(ZnO), tin oxide (SnO₂), or the like. In exemplary embodiments, thetouch electrodes SS1 are made of a single-layer or a multi-layer. Theconductive polymer may include polythiophene compound, polypyrrolecompound, polyaniline compound, polyacetylene compound, polyphenylenecompound, and a mixture thereof, or the like, particularly PEDOT/PSScompound of polythiophene compound. Since the conductive polymer notonly is easily manufactured, but also has higher flexibility thanconductivity metal oxide, e.g., ITO, the probability of a crackoccurring when bending may be decreased.

The touch electrodes SS1 and the wires TRL may be realized as a separatesubstrate SUB, or on various elements included in the display device DP.For example, the touch electrodes SS1 and the wires TRL may be formed onthe display unit PP used in the display device DP.

In the case where the touch electrodes SS1 and the wires TRL arerealized as the separate substrate SUB, the substrate SUB may be made ofan insulating material such as glass, resin, or the like. In addition,the substrate SUB may be made of a flexible material to be bent orfolded, and may have a single-layer structure or a multi-layerstructure. For example, the substrate SUB may include at least oneselected from polystyrene, polyvinyl alcohol, polymethyl methacrylate,polyethersulfone, polyacrylate, polyetherimide, polyethylenenaphthalate, polyethylene terephthalate, polyphenylene sulfide,polyarylate, polyimide, polycarbonate, triacetate cellulose, andcellulose acetate propionate. However, the material forming thesubstrate SUB may be variously changed, and the substrate SUB may bemade of a glass fiber reinforced plastics (GFRP), or the like.

The wires TRL may be disposed between the touch electrodes SS1 and thepads TRP so as to connect the touch electrodes SS1 and the pads TRP eachother. In addition, the wires TRL may be connected to the sensor controlunit SC through the pads TRP. For example, the pads TRP may be connectedto a sensor control unit SC through a separate wire, a flexible printedcircuit substrate, a tape carrier package, a connector, a chip on film,or the like.

Since a self-capacitance of the touch electrodes SS1, which isassociated with a touch, is varied when the touch is input in the firstsensor S1, the sensor control unit SC may detect a touch position byusing a signal output from the touch electrodes SS1.

Referring to FIG. 8B, the first sensor S1 according to exemplaryembodiments may be a sensor of a mutual-capacitance type.

In addition, the first sensor S1 may include first touch electrodes SSa,second touch electrodes SSb, wires TRL, and pads TRP disposed at oneends of wires TRL.

The first touch electrodes SSa may be longitudinally formed in onedirection and may be arranged in plural in the other directionintersecting the one direction. The second touch electrodes SSb aredisposed to be spaced apart the first touch electrodes SSa, therebyfunctioning as a sensor of a mutual-capacitance type with the firsttouch electrodes SSa. For this purpose, the second touch electrodes SSbmay be disposed so as to intersect with the first touch electrodes SSa.For example, the second touch electrodes SSb may be longitudinallyformed in the other direction and may be arranged in plural in the onedirection.

In exemplary embodiments, the first touch electrodes SSa and the secondtouch electrodes SSb are shown and described as having a diamond shape,but their shapes are not so limited and may be variously changed. Forexample, each of the first touch electrodes SSa and the second touchelectrodes SSb may have a circle shape. In addition, each of the firsttouch electrodes SSa may have an elongated, stripe-type shape extendingin one direction, each of the second touch electrodes SSb may have anelongated, stripe-type shape extending in other direction intersectingthe first touch electrodes SSa.

Since the first touch electrodes SSa and the second touch electrodes SSbare disposed as described above, a mutual capacitance is formed betweenthe first touch electrodes SSa and the second touch electrodes SSb, andthe mutual capacitance associated with a touch is varied when the touchis input in the first sensor S1. In order to prevent a contact betweenthe first touch electrodes SSa and the second touch electrodes SSb, aninsulating layer is disposed between the first touch electrodes SSa andthe second touch electrodes SSb. The insulating layer may be formedentirely between the first touch electrodes SSa and the second touchelectrodes SSb, or may be formed only at each of cross-regions betweenthe first touch electrodes SSa and the second touch electrodes SSb.

The first touch electrodes SSa and the second touch electrodes SSb maybe made of a transparent conductive material, or of other conductivematerial such as an opaque metal, etc. For example, the first touchelectrodes SSa and the second touch electrodes SSb may be formed of thesame material as the touch electrode described above.

The first touch electrodes SSa and the second touch electrodes SSb areshown and described as having a rectangular shape in FIG. 8B, but theshape of the first touch electrodes SSa and the second touch electrodesSSb may be variously changed. In addition, the first touch electrodesSSa and the second touch electrodes SSb may have a mesh structure to addflexibility.

The wires TRL may be disposed between the touch electrodes SS1 and thepads TRP so as to connect the touch electrodes SS1 and the pads TRP toeach other. In addition, the wires TRL may be connected to the sensorcontrol unit SC through the pads TRP. For example, the pads TRP may beconnected to a sensor control unit SC through a separate wire, aflexible printed circuit substrate, a tape carrier package, a connector,a chip on film, or the like.

The first touch electrodes SSa may receive a driving signal from thesensor control unit SC, and the second touch electrodes SSb may output asensing signal applying a variation of a capacitance to the sensorcontrol unit SC. Accordingly, the sensor control unit SC may detect atouch position by using a sensing signal output from the second touchelectrodes SSb.

The display device DP according to exemplary embodiments may furtherinclude other sensor sensing a touch pressure of a user in addition tothe elements described above.

FIG. 9 is a cross-sectional view of another exemplary display device DPtaken along a line corresponding to a line I-I′ of FIG. 1. FIG. 10 is ablock diagram graphically illustrating some of the components of anexemplary display device DP according to exemplary embodiments.

Referring to FIGS. 9 and 10, a display panel PNL of the display deviceDP according to exemplary embodiments includes a substrate SUB, adisplay unit PP disposed on a front surface of the substrate SUB, afirst sensor S1 disposed on the display unit PP, a buffering member BFMdisposed on the first sensor S1, a second sensor S2 disposed on thebuffering member BFM, and the fingerprint sensor FPS disposed on a rearsurface of the substrate SUB.

Since the substrate SUB, the display unit PP, the fingerprint sensorFPS, and the first sensor S1 may be substantially the same as theexemplary embodiments described above, detailed descriptions thereof areomitted, and only differences from the exemplary embodiments describedabove will be mainly described.

The second sensor S2 is a sensor for sensing a touch press when a usertouches. The second sensor S2 may be a sensor of various types, forexample, a sensor of a capacitive type sensing a capacitance between thefirst sensor S1 and the second sensor S2.

In exemplary embodiments, the type of the first sensor S1 and the secondsensor S2 may be different from the type of the fingerprint sensor. Forexample, while the fingerprint sensor may be a sensor using light or anultrasonic wave, or the first sensor S1 and the second sensor S2 may bea sensor sensing a capacitance variation. In addition, the sensing typeof the first sensor S1 may be the same as or different from the sensingtype of the second sensor S2.

For example, the first sensor S1 may be a sensor of a mutual-capacitancetype, and the second sensor S2 may be a sensor of a mutual force sensorresistor (FSR). In exemplary embodiments, a case where the second sensorS2 is a capacitive type sensor sensing a capacitance between the firstsensor S1 and the second sensor S2 will be described as an example.

A buffering member BFM may be disposed between the first sensor S1 andthe second sensor S2. Thus, the buffering member BFM contacts the firstsensor S1 and the second sensor S2.

The buffering member BFM may serve to buffer an external impact, and mayhave an elastic force for this purpose. For example, the bufferingmember BFM may be varied by an external pressure, and when the externalpressure is removed, the buffering member BFM may have an elastic forcebeing capable of restoring itself to its original state again.

In addition, the buffering member BFM may be formed of an insulationmaterial to prevent an electric short between the first sensor S1 andthe second sensor S2.

The buffering member BFM may be made of a porous polymer so as to havean elastic force. For example, the buffering member BFM may have foamshape like sponge. For example, the buffering member BFM may includethermoplastic elastomer, polystyrene, polyolefin, polyurethanethermoplastic elastomers, polyamides, synthetic rubbers,polydimethylsiloxane, polybutadiene, polyisobutylene,poly(styrene-butadienestyrene), polyurethanes, polychloroprene,polyethylene, silicone, etc. and compositions thereof, but is notlimited thereto.

The buffering member BFM according to exemplary embodiments may besingle or a plurality of divided shapes. That is, the buffering membersmay be divided from each other and may have various shapes.

In exemplary embodiments, the case where the buffering member BFM isformed has been described, but the inventive embodiments are not limitedthereto. For example, an air layer may be formed instead of thebuffering member BFM.

According to exemplary embodiments, the sensor control unit SC maycontrol an operation of the fingerprint sensor FPS, the first sensor S1,and the second sensor S2. The sensor control unit SC may sense lightvariation of the fingerprint sensor FPS, thereby sensing a fingerprintof a user, and may sense a capacitance, etc. of the first sensor S1,thereby sensing a touch position based on a user touch. In addition, thesensor control unit SC may sense a capacitance, etc. of the secondsensor S2, thereby sensing a touch pressure based on the user touch.

According to exemplary embodiments, the sensor control unit SC maysimultaneously drive or sequentially drive the operation of thefingerprint sensor FPS, the first sensor S1, and the second sensor S2.

When the second sensor S2 is pressed by the touch of a user, etc., thethickness of the buffering member BFM between the first sensor S1 andthe second sensor S2 may vary. Thus, the capacitance between the firstsensor S1 and the second sensor S2 may vary. Therefore, the intensity ofa pressure may be detected by using a capacitance variation of thesecond sensor S2.

The pressure applied to the second sensor S2 may be mainly generated bythe touch of the user, but is not limited thereto, and may be generatedby other various means known in the art.

The sensor control unit SC may sense capacitance variation between thefirst sensor S1 and the second sensor S2, thereby detecting a pressureapplied to the second sensor S2.

As shown in FIG. 9, in the case that the first sensor S1 and the secondsensor S2 are disposed inside the display panel PNL, the first sensor S1and the second sensor S2 may be integrated with the display panel PNL.Accordingly, an undesirable substrate SUB or layer may be removed,thereby reducing a thickness of the display device DP and amanufacturing cost.

FIGS. 11A to 11C are plan views illustrating a second sensor S2according to exemplary embodiments.

Referring to FIG. 11A, the second sensor S2 according to exemplaryembodiments may include a touch electrode SS, a wire TRL, and pad TRPdisposed in one end of the wire TRL

The touch electrode SS may cover all or most of the first area A1 andthe second area A2 and be formed as an inseparable integral shape, e.g.,a planar shape.

In exemplary embodiments, an identification pattern may be disposed inthe first area A1 or in a portion adjacent to the first area A1 in thesecond area A2 so that the position of a fingerprint sensing area, i.e.,the first area A1 is recognized to a user. The identification patternfunctions effectively as long as the user may identify the first areaA1, and the shape or position thereof is not so limited. For example,the identification pattern may be disposed along an edge of the firstarea A1, and the identification pattern may be formed as a black matrix.In exemplary embodiments, when the identification pattern is formed as ablack matrix, the identification pattern may be formed with anotherblack matrix, which shields light in other area, in a rear surface of awindow.

The touch electrode SS may include a conductive material. For example,the conductive material may include a metal, an alloy thereof, aconductive polymer, a conductive metal oxide, or the like. In exemplaryembodiments, the metal may include copper, silver, gold, platinum,palladium, nickel, tin, aluminum, cobalt, rhodium, iridium, iron,ruthenium, osmium, manganese, molybdenum, tungsten, niobium, tantalum,titanium, bismuth, antimony, lead, or the like. The conductive metaloxide may include indium tin oxide (ITO), indium zinc oxide (IZO),antimony zinc oxide (AZO), indium tin zinc oxide (ITZO), zinc oxide(ZnO), tin oxide (SnO₂), or the like. In exemplary embodiments, thetouch electrodes SS1 are made of a single-layer or a multi-layer.

In exemplary embodiments, the conductive polymer may includepolythiophene compound, polypyrrole compound, polyaniline compound,polyacetylene compound, polyphenylene compound, and a mixture thereof,or the like, particularly PEDOT/PSS compound of polythiophene compound.The conductive polymer may be easily manufactured by using wet-coating,and may be particularly manufactured by using a roll-to-roll method.

Since the conductive polymer has higher flexibility than conductivitymetal oxide, e.g., ITO, a probability of a crack may be decreased whenbending.

Particularly, the PEDOT/PSS compound may have a relatively lowerresistance and a relatively higher light transmittance. In addition,since the conductive polymer has a refractive index similar to that ofthe substrate SUB or an adhesive, the relative light loss may be small.In exemplary embodiments, since the sheet resistance and the lighttransmittance of a layer, which is made of PEDOT/PSS, may havesubstantially the same as the sheet resistance and the lighttransmittance a conductive layer made of indium-tin-oxide respectively,the layer may have a sheet resistance of about 100 W/sq to about 300W/sq, preferably 150 W/sq and a light transmittance of more than about80%, preferably more than about 88%. In addition, PEDOT/PSS may have ahaze of 0.4% and a light loss rate of about 4.1%.

The wire TRL may be disposed between the touch electrode SS and the padTRP so to connect the touch electrode SS and the pad TRP to each other.In addition, the wire TRL may be connected to the sensor control unit SCthrough the pad TRP. For example, the pad TRP may be connected to asensor control unit SC through a separate wire, a flexible printedcircuit substrate, a tape carrier package, a connector, a chip on film,or the like.

In exemplary embodiments, the touch electrode SS of the second sensor S2may have various shapes.

Referring to FIG. 11B, the second sensor S2 according to exemplaryembodiments may be formed from a plurality of touch electrodes SS2 in asimilar manner as a touch sensor of a self-capacitance type. That is,the second sensor S2 may include a plurality of touch electrodes SS2, aplurality of wires TRL, and a plurality of pads TRP disposed in one endsof the wires TRL.

In exemplary embodiments, the second sensor S2 may include the pluralityof touch electrodes SS2, thereby sensing pressure of a multi-touch aswell as a single-touch.

The second sensor S2 may have a structure capable of sensing a singlecapacitance variation or a plurality of capacitance variations with thefirst sensor S1, but the configuration of the second sensor S2 is notlimited thereto. For example, the second sensor S2 may have a shapesimilar to that of a mutual-capacitance type touch sensor.

Referring to FIG. 11C, the second sensor S2 according to exemplaryembodiments may be similar to that of FIG. 11A, but the touch electrodeSS3 may be divided into one portion in the first area A1 and the otherportion in the second area A2. An identification pattern may be disposedin a portion of the first area A1 and the second area A2 separated fromeach other, for example, in the first area A1 or in a portion of thesecond area A2 adjacent to the first area A1 so that the position of afingerprint sensing area, i.e., the first area A1 is recognized by auser. The identification pattern functions effectively as long as theuser may identify the first area A1, but the shape or position thereofis not so limited. For example, the identification pattern may bedisposed along an edge of the first area A1, and the identificationpattern may be formed as a black matrix.

The touch electrode SS3 of the first area A1 and the segregated secondarea A2 may be electrically connected to each other through a separatewire, etc. Alternatively, each of the touch electrodes SS3 of the firstarea A1 and the segregated second area A2 may be connected to the sensorcontrol unit SC through a separate wire, etc.

The display device DP according to exemplary embodiments may sense afingerprint, a touch position, and/or a touch pressure in various waysby using the fingerprint sensor FPS, the first sensor S1, and the secondsensor S2.

FIG. 12 is a cross-sectional view of another exemplary display device DPtaken along a line corresponding to a line I-I′ of FIG. 1. FIG. 13 is aplan view illustrating a first sensor S1 in the display device of FIG.12.

A display panel PNL of the display device DP according to exemplaryembodiments includes a substrate SUB, a display unit PP disposed on afront surface of the substrate SUB, a first sensor S1 disposed on thedisplay unit PP, a buffering member BFM disposed on the first sensor S1,a second sensor S2 disposed on the buffering member BFM, and thefingerprint sensor FPS disposed on a rear surface of the substrate SUB.

Since the substrate SUB, the display unit PP, the fingerprint sensorFPS, and the second sensor S2 may be substantially the same as theexemplary embodiments described above, detailed descriptions thereof areomitted, and the differences from the exemplary embodiments describedabove will be mainly described.

In exemplary embodiments, the first sensor S1 may be described as asensor of a self-capacitance type for convenience of description, but isnot limited thereto and the first sensor S1 may be a sensor of varioustypes. For example, the first sensor S1 may be a sensor of amutual-capacitance type.

In exemplary embodiments, the first sensor S1 may be substantiallydisposed only in the second area A2 of the first area A1 and the secondarea A2. In the first sensor S1, the first area A1 has a hole HL, andthe first sensor S1 is not disposed in the hole HL. That is, the touchelectrodes SS1 of the first sensor S1 are not formed in the hole HL ofthe first area A1.

According to exemplary embodiments, in the first area A1, thefingerprint sensor FPS may be used as the touch position sensor, and thesecond sensor S2 defines a capacitance with a conductor disposed in thefingerprint sensor FPS, thereby sensing a pressure. In other words, afingerprint of a user may be recognized by using the fingerprint sensordisposed in the first area A1, but a touch position and a touch pressuremay be recognized by using different sensors in the first area A1 andthe second area A2. That is, in the first area A1, the touch positionmay be sensed by using the fingerprint sensor FPS, and the touchpressure may be sensed by using the fingerprint sensor FPS and thesecond sensor S2. In the second area A2, the touch position may besensed by using the first sensor S1, and the touch pressure may besensed by using the first sensor S1 and the second sensor S2.

In the display device DP according to exemplary embodiments describedabove, at least a portion of the display device DP may have flexibilityor not have flexibility. Elements including in the display device DP,for example, the display panel PNL or the window WD may also separatelyhave flexibility so that the display device DP may have flexibility. Forexample, the display device DP may include a flexible area havingflexibility and/or a rigid area having no flexibility depending on adegree of flexibility. In the case where the display device DP hasflexibility, the display device DP may be folded. If a virtual line overwhich the display device DP is folded is called as a folding line, thefolding line may be disposed in the flexible area.

Herein, the term “may be folded” does not necessarily mean a generalfolded state of an object and is not limited to a fixed form; rather, itmay include a state in which a certain form may change into anotherform. For example, “may be folded” may refer to being folded, bended,curved, or rolled along at least one predetermined line, that is, thefolding line. Therefore, the display device DP may have flexibility,even if it may be not folded or may be actually folded in the flexiblearea.

Herein, in the flexible area and the rigid area, the terms as “havingflexibility” or “not having flexibility” and “flexible” or “rigid” areexpressions relatively showing properties of the display device DP. Morespecifically, the expressions “not having flexibility” and “rigid” referto not only those instances where a material does not have flexibilityat all and thus is hard, but also to those instances where a materialhas flexibility that is less than that of the flexible area.Accordingly, the rigid area may have relatively small flexibilitycompared to the flexible area or may not have any flexibility. Even upona condition that the flexible area is folded, the rigid area may not befolded.

In exemplary embodiments, the folding line, the flexible area, or therigid area may be variously changed. For example, the display device DPmay include both the flexible area and the rigid area, but may includeonly the flexible except the rigid area. In addition, single or pluralfolding lines may be provided. If necessary, the folding line may beprovided in various positions along the display, and in this case, thedisplay device DP may be entirely rolled.

FIG. 14 is a perspective view illustrating a display device DPconstructed according to the principles of the invention, FIG. 15A is across-sectional view illustrating the display device DP of FIG. 14 in afolded position, and FIG. 15B is a cross-sectional view illustrating thedisplay device DP of FIG. 14 in a rolled position.

As shown in FIG. 14, the display device DP may be formed as a flatshape, but at least a portion of the display device DP may vary, therebybeing formed as other shape.

Referring to FIGS. 15A and 15B together with FIG. 14, at least a portionof the display device DP in exemplary embodiments may have flexibility,or the entire display device DP may have flexibility.

Since the display device DP has flexibility, the display device DP isfolded as shown in FIG. 14A or is rolled as shown in FIG. 14B in aflexible area.

The folding line, in which the display device DP is folded, may passthrough a center portion of the display device DP and may be parallelwith the second direction D2. However, the position of the folding lineis not limited thereto. The folding line may be disposed in a directionparallel with the first direction D1 and may be disposed in an inclineddirection with reference to the first direction D1 or the seconddirection D2. In addition, it is needless to say that the folding lineneed not pass through the center of the display device DP. Further, whenbeing folded about the folding line, the display device DP may be foldedso that a front surface displaying an image becomes an inner side or anouter side. Alternatively, when the display device DP is folded about aplurality of folding lines, one portion thereof may be folded so thatthe front surface becomes the inner side and other portion thereof maybe folded so that the front surface becomes the outer side.

Reference number D3 means a third direction perpendicular to each of thefirst direction and the second direction.

The display device DP may be rolled so that one side faces other side. Arolling direction of the display device DP may be the first direction D1or the second direction D2. However, the rolling direction is notlimited thereto and may be an inclined direction with reference to thefirst direction D1 or the second direction D2. In addition, in thedisplay device DP, a rolling area may be a portion of the display deviceDP, and an entire area thereof may be also rolled.

As described above, exemplary embodiments of the invention provide adisplay device capable of enhancing a security function by including afingerprint sensor having improved sensitivity. Further, exemplaryembodiments provide a high-quality display device in which resolution ofthe area including the fingerprint sensor is substantially the same asresolution of an area not including the fingerprint sensor.

In addition, exemplary embodiments provide a display device which iscapable of sensing a touch position and a touch pressure while alsosensing the fingerprint, whereby enhancing a convenience of use.

The display device according to exemplary embodiments may be applied tovarious electronic devices. For example, the display device may beapplied to various wearable devices such as a television, a laptop, amobile phone, a smart phone, a smart pad, a PMP, a PDA, a navigationsystem, a smart watch, etc.

Although certain exemplary embodiments and implementations have beendescribed herein, other embodiments and modifications will be apparentfrom this description. Accordingly, the inventive concepts are notlimited to such embodiments, but rather to the broader scope of thepresented claims and various obvious modifications and equivalentarrangements.

What is claimed is:
 1. A display device comprising: a substrateincluding, in a plan view, a first area having a first lighttransmittance and a second area adjacent to the first area with a secondlight transmittance; a plurality of pixels disposed on the substrate todisplay an image; a photo sensor disposed in the first area below thesubstrate; an insulating layer on the substrate; a pixel defining layeron the substrate; and a passivation layer on the substrate, wherein thefirst light transmittance is greater than the second lighttransmittance, wherein the first area includes a light emitting areahaving a first size and a light transmission area having a second sizethrough which light is transmitted, the light transmission area beingdifferent from the light emitting area, wherein the first size issmaller than the second size to improve sensitivity of the photo sensor,wherein the plurality of pixels include at least one first pixel in thefirst area and a second pixel in the second area, wherein the firstpixel includes the light emitting area and the light transmission area,wherein the first pixel includes at least one first sub-pixel disposedin the light emitting area, wherein the first sub-pixel comprises: afirst electrode disposed on the substrate; an emission layer disposed onthe first electrode; and a second electrode disposed on the emissionlayer, wherein the insulating layer is disposed between the substrateand the first electrode, wherein the insulating layer extends into thelight transmission area, wherein the insulating layer overlaps the pixeldefining layer and the passivation layer in the light transmission areain a plan view, wherein the first sub-pixel further includes at leastone structure selected from the group of a hole injection layer, a holetransport layer, an electron transport layer, and an electron injectionlayer, the at least one structure being disposed between the firstelectrode and the second electrode, and wherein the at least onestructure extends across the light transmission area.
 2. The displaydevice of claim 1, wherein the second pixel includes at least one secondsub-pixel, and wherein each of the first sub-pixel and the secondsub-pixel emits one wavelength of light selected from the group of redlight, green light, and blue light.
 3. The display device of claim 2,wherein a size of the first pixel is substantially the same as a size ofthe second pixel.
 4. The display device of claim 1, wherein the secondpixel includes at least one second sub-pixel, and wherein a size of thefirst sub-pixel is smaller than a size of the second sub-pixel.
 5. Thedisplay device of claim 1, further comprising a first sensor disposedabove the substrate to sense a touch position input by a user, whereinthe first sensor is a touch sensor of a self-capacitance type or a touchsensor of a mutual-capacitance type, wherein the first sensor includes:a first touch electrode; and a second touch electrode spaced apart fromthe first touch electrode and forming a capacitance with the first touchelectrode, and wherein a portion of the first and second touchelectrodes does not overlap the first area in the plan view.
 6. Adisplay device comprising: a substrate including, in a plan view, afirst area having a first light transmittance and a second area adjacentto the first area with a second light transmittance; a plurality ofpixels disposed on the substrate to display an image; an insulatinglayer on the substrate; a pixel defining layer on the substrate; and apassivation layer on the substrate, wherein the first lighttransmittance is greater than the second light transmittance, whereinthe first area includes a light emitting area having a first size and alight transmission area having a second size through which light istransmitted, the light transmission area being different from the lightemitting area, wherein the first size is smaller than the second size,wherein the plurality of pixels include at least one first pixel in thefirst area and a second pixel in the second area, wherein the firstpixel includes the light emitting area and the light transmission area,wherein the first pixel includes at least one first sub-pixel disposedin the light emitting area, wherein the first sub-pixel comprises: afirst electrode disposed on the substrate; an emission layer disposed onthe first electrode; and a second electrode disposed on the emissionlayer, wherein the insulating layer is disposed between the substrateand the first electrode, wherein the insulating layer extends into thelight transmission area, wherein the insulating layer overlaps the pixeldefining layer and the passivation layer in the light transmission areain a plan view, wherein the first sub-pixel further includes at leastone structure selected from the group of a hole injection layer, a holetransport layer, an electron transport layer, and an electron injectionlayer, the at least one structure being disposed between the firstelectrode and the second electrode, and wherein the at least onestructure extends across the light transmission area.
 7. The displaydevice of claim 6, wherein the second pixel includes at least one secondsub-pixel, and wherein each of the first sub-pixel and the secondsub-pixel emits one wavelength of light selected from the group of redlight, green light, and blue light.
 8. The display device of claim 7,wherein a size of the first pixel is substantially the same as a size ofthe second pixel.
 9. The display device of claim 7, further comprising aphoto sensor disposed in the first area below the substrate.
 10. Thedisplay device of claim 6, wherein the second sub-pixel includes atleast one second sub-pixel, and wherein a size of the first sub-pixel issmaller than a size of the second sub-pixel.
 11. The display device ofclaim 6, further comprising a first sensor disposed above the substrateto sense a touch position input by a user, wherein the first sensor is atouch sensor of a self-capacitance type or a touch sensor of amutual-capacitance type, wherein the first sensor includes: a firsttouch electrode; and a second touch electrode spaced apart from thefirst touch electrode and forming a capacitance with the first touchelectrode, and wherein a portion of the first and second touchelectrodes does not overlap the first area in the plan view.
 12. Adisplay device comprising: a substrate including, in a plan view, afirst area having a first light transmittance and a second area adjacentto the first area with a second light transmittance; a plurality ofpixels disposed on the substrate to display an image; a plurality ofthin film transistors disposed on the substrate, each of the pluralityof thin film transistors comprising an active layer, a gate electrode, asource electrode, and a drain electrode; a photo sensor disposed in thefirst area below the substrate; an insulating layer on the substrate; apixel defining layer on the substrate; and a passivation layer on thesubstrate, wherein the first light transmittance is greater than thesecond light transmittance, wherein the first area includes a lightemitting area having a first size and a light transmission area having asecond size through which light is transmitted, the light transmissionarea being different from the light emitting area, wherein the firstsize is smaller than the second size to improve sensitivity of the photosensor, wherein the plurality of pixels include at least one first pixelin the first area and a second pixel in the second area, wherein thefirst pixel includes the light emitting area and the light transmissionarea, wherein the first pixel includes at least one first sub-pixeldisposed in the light emitting area, wherein the first sub-pixelcomprises: a first electrode disposed on the substrate; an emissionlayer disposed on the first electrode; and a second electrode disposedon the emission layer, wherein the insulating layer is disposed betweenthe active layer and the first electrode, wherein the first sub-pixelfurther includes at least one structure selected from the group of ahole injection layer, a hole transport layer, an electron transportlayer, and an electron injection layer, the at least one structure beingdisposed between the first electrode and the second electrode, whereinthe at least one structure extends across the light transmission area,and wherein a portion of the insulating layer is not disposed in thelight transmission area in the first area.
 13. The display device ofclaim 12, wherein the second pixel includes at least one secondsub-pixel, and wherein each of the first sub-pixel and the secondsub-pixel emits one wavelength of light selected from the group of redlight, green light, and blue light.
 14. The display device of claim 13,wherein a size of the first sub-pixel is smaller than a size of thesecond sub-pixel.
 15. The display device of claim 14, further comprisinga first sensor disposed on the substrate to sense a touch position inputby a user, wherein the first sensor is a touch sensor of aself-capacitance type or a touch sensor of a mutual-capacitance type,wherein the first sensor includes: a first touch electrode; and a secondtouch electrode spaced apart from the first touch electrode and forminga capacitance with the first touch electrode, and wherein each of thefirst touch electrode and the second touch electrode comprises a meshstructure.
 16. The display device of claim 15, wherein a portion of thefirst sensor and the first area are not overlapped in the plan view. 17.A display device comprising: a substrate including, in a plan view, afirst area having a first light transmittance and a second area adjacentto the first area with a second light transmittance; a plurality ofpixels disposed on the substrate to display an image; a plurality ofthin film transistors disposed on the substrate, each of the pluralityof thin film transistors comprising an active layer, a gate electrode, asource electrode, and a drain electrode; a photo sensor disposed in thefirst area below the substrate; an insulating layer on the substrate; apixel defining layer on the substrate; and a passivation layer on thesubstrate, wherein the first light transmittance is greater than thesecond light transmittance, wherein the first area includes a lightemitting area having a first size and a light transmission area having asecond size through which light is transmitted, the light transmissionarea being different from the light emitting area, wherein the firstsize is smaller than the second size to improve sensitivity of the photosensor, wherein the plurality of pixels include at least one first pixelin the first area and a second pixel in the second area, wherein thefirst pixel includes the light emitting area and the light transmissionarea, wherein the at least one first pixel includes at least one firstsub-pixel disposed in the light emitting area, wherein the firstsub-pixel comprises: a first electrode disposed on the substrate; anemission layer disposed on the first electrode; and a second electrodedisposed on the emission layer, wherein the insulating layer is disposedbetween the active layer and the first electrode, wherein thepassivation layer is disposed between the source electrode or the drainelectrode and the first electrode, wherein the first sub-pixel furtherincludes at least one structure selected from the group of a holeinjection layer, a hole transport layer, an electron transport layer,and an electron injection layer, the at least one structure beingdisposed between the first electrode and the second electrode, whereinthe at least one structure extends across the light transmission area,wherein a portion of the insulating layer is not disposed in the lighttransmission area in the first area, and wherein a portion of thepassivation layer is not disposed in the light transmission area in thefirst area.
 18. The display device of claim 17, wherein the second pixelincludes at least one second sub-pixel, and wherein each of the firstsub-pixel and the second sub-pixel emits one wavelength of lightselected from the group of red light, green light, and blue light. 19.The display device of claim 18, wherein a size of the first sub-pixel issmaller than a size of the second sub-pixel.
 20. The display device ofclaim 17, further comprising a first sensor disposed on the substrate tosense a touch position input by a user, wherein the first sensor is atouch sensor of a self-capacitance type or a touch sensor of amutual-capacitance type, wherein the first sensor includes: a firsttouch electrode; and a second touch electrode spaced apart from thefirst touch electrode and forming a capacitance with the first touchelectrode, and wherein each of the first touch electrode and the secondtouch electrode comprises a mesh structure.
 21. The display device ofclaim 17, wherein a portion of the second electrode is not disposed inthe light transmission area in the first area.
 22. A display devicecomprising: a substrate including, in a plan view, a first area having afirst light transmittance and a second area adjacent to the first areawith a second light transmittance; a plurality of pixels disposed on thesubstrate to display an image; a plurality of thin film transistorsdisposed on the substrate, each of the plurality of thin filmtransistors comprising an active layer, a gate electrode, a sourceelectrode, and a drain electrode; an insulating layer on the substrate;a pixel defining layer on the substrate; and a passivation layer on thesubstrate, wherein the first light transmittance is greater than thesecond light transmittance, wherein the first area includes a lightemitting area having a first size and a light transmission area having asecond size through which light is transmitted, the light transmissionarea being different from the light emitting area, wherein the firstsize is smaller than the second size, wherein the plurality of pixelsinclude at least one first pixel in the first area and a second pixel inthe second area, wherein the first pixel includes the light emittingarea and the light transmission area, wherein the first pixel includesat least one first sub-pixel disposed in the light emitting area,wherein the first sub-pixel comprises: a first electrode disposed on thesubstrate; an emission layer disposed on the first electrode; and asecond electrode disposed on the emission layer, wherein the insulatinglayer is disposed between the active layer and the first electrode,wherein the passivation layer is disposed between the source electrodeor the drain electrode and the first electrode, wherein the firstsub-pixel further includes at least one structure selected from thegroup of a hole injection layer, a hole transport layer, an electrontransport layer, and an electron injection layer, the at least onestructure being disposed between the first electrode and the secondelectrode, wherein the at least one structure extends across the lighttransmission area, wherein a portion of the insulating layer is notdisposed in the light transmission area in the first area, and wherein aportion of the passivation layer is not disposed in the lighttransmission area in the first area.
 23. The display device of claim 22,wherein the second pixel includes at least one second sub-pixel, andwherein each of the first sub-pixel and the second sub-pixel emits onewavelength of light selected from the group of red light, green light,and blue light.
 24. The display device of claim 23, wherein a size ofthe first sub-pixel is smaller than a size of the second sub-pixel. 25.The display device of claim 24, further comprising a first sensordisposed on the substrate to sense a touch position input by a user,wherein the first sensor is a touch sensor of a self-capacitance type ora touch sensor of a mutual-capacitance type, wherein the first sensorincludes: a first touch electrode; and a second touch electrode spacedapart from the first touch electrode and forming a capacitance with thefirst touch electrode, and wherein each of the first touch electrode andthe second touch electrode comprises a mesh structure.
 26. The displaydevice of claim 22, wherein a portion of the second electrode is notdisposed in the light transmission area in the first area.
 27. A displaydevice comprising: a substrate including, in a plan view, a first areahaving a first light transmittance and a second area adjacent to thefirst area with a second light transmittance; a plurality of pixelsdisposed on the substrate to display an image; a plurality of thin filmtransistors disposed on the substrate, each of the plurality of thinfilm transistors comprising an active layer, a gate electrode, a sourceelectrode, and a drain electrode; a photo sensor disposed in the firstarea below the substrate, an insulating layer on the substrate; a pixeldefining layer on the substrate; a passivation layer on the substrate;and a first sensor disposed on the substrate to sense a touch positioninput by a user, wherein the first light transmittance is greater thanthe second light transmittance to improve sensitivity of the photosensor, wherein the plurality of pixels include at least one first pixelin the first area and a second pixel in the second area, wherein thefirst pixel includes a light emitting area and a light transmissionarea, wherein the at least one first pixel includes at least one firstsub-pixel disposed in the light emitting area, wherein the firstsub-pixel comprises: a first electrode disposed on the substrate; anemission layer disposed on the first electrode; and a second electrodedisposed on the emission layer, wherein the insulating layer is disposedbetween the active layer and the first electrode, wherein thepassivation layer is disposed between the source electrode or the drainelectrode and the first electrode, wherein the first sub-pixel furtherincludes at least one structure selected from the group of a holeinjection layer, a hole transport layer, an electron transport layer,and an electron injection layer, the at least one structure beingdisposed between the first electrode and the second electrode, wherein aportion of the insulating layer is not disposed in the lighttransmission area in the first area, wherein a portion of thepassivation layer is not disposed in the light transmission area in thefirst area, wherein a portion of the second electrode is not disposed inthe light transmission area in the first area, wherein the second pixelincludes at least one second sub-pixel, wherein each of the firstsub-pixel and the second sub-pixel emits one wavelength of lightselected from the group of red light, green light, and blue light,wherein the first sensor is a touch sensor of a self-capacitance type ora touch sensor of a mutual-capacitance type, wherein the first sensorincludes: a first touch electrode; and a second touch electrode spacedapart from the first touch electrode and forming a capacitance with thefirst touch electrode, and wherein each of the first touch electrode andthe second touch electrode comprises a mesh structure.
 28. The displaydevice of claim 27, wherein a size of the first sub-pixel is smallerthan a size of the second sub-pixel.
 29. The display device of claim 28,wherein a size of the first pixel is substantially the same as a size ofthe second pixel.
 30. A display device comprising: a substrateincluding, in a plan view, a first area having a first lighttransmittance and a second area adjacent to the first area with a secondlight transmittance; a plurality of pixels disposed on the substrate todisplay an image; a plurality of thin film transistors disposed on thesubstrate, each of the plurality of thin film transistors comprising anactive layer, a gate electrode, a source electrode, and a drainelectrode; an insulating layer on the substrate; a pixel defining layeron the substrate; a passivation layer on the substrate; and a firstsensor disposed on the substrate to sense a touch position input by auser, wherein the first light transmittance is greater than the secondlight transmittance, wherein the plurality of pixels include at leastone first pixel in the first area and a second pixel in the second area,wherein the first pixel includes a light emitting area and a lighttransmission area, wherein the first pixel includes at least one firstsub-pixel disposed in the light emitting area, wherein the firstsub-pixel comprises: a first electrode disposed on the substrate; anemission layer disposed on the first electrode; and a second electrodedisposed on the emission layer, wherein the insulating layer is disposedbetween the active layer and the first electrode, wherein thepassivation layer is disposed between the source electrode or the drainelectrode and the first electrode, wherein the first sub-pixel furtherincludes at least one structure selected from the group of a holeinjection layer, a hole transport layer, an electron transport layer,and an electron injection layer, the at least one structure beingdisposed between the first electrode and the second electrode, wherein aportion of the insulating layer is not disposed in the lighttransmission area in the first area, wherein a portion of thepassivation layer is not disposed in the light transmission area in thefirst area, wherein a portion of the second electrode is not disposed inthe light transmission area in the first area, wherein the firstsub-pixel emits one wavelength of light selected from the group of redlight, green light, and blue light, wherein the first sensor is a touchsensor of a self-capacitance type or a touch sensor of amutual-capacitance type, wherein the first sensor includes: a firsttouch electrode; and a second touch electrode spaced apart from thefirst touch electrode and forming a capacitance with the first touchelectrode, and wherein each of the first touch electrode and the secondtouch electrode comprises a mesh structure.
 31. The display device ofclaim 30, wherein the second pixel includes at least one secondsub-pixel, and a size of the at least one first sub-pixel is smallerthan a size of the second sub-pixel.
 32. The display device of claim 31,wherein a size of the first pixel is substantially the same as a size ofthe second pixel.
 33. The display device of claim 30, further comprisinga photo sensor disposed in the first area below the substrate.
 34. Thedisplay device of claim 30, wherein a portion of the first sensor andthe first area are not overlapped in the plan view.
 35. A display devicecomprising: a substrate including, in a plan view, a first area having afirst light transmittance and a second area adjacent to the first areawith a second light transmittance; a plurality of pixels disposed on thesubstrate to display an image; and a first sensor disposed on thesubstrate to sense a touch position input by a user, wherein the firstlight transmittance is greater than the second light transmittance,wherein the first area includes a light emitting area having a firstsize and a light transmission area having a second size through whichlight is transmitted, the light transmission area being different fromthe light emitting area, wherein the first size is smaller than thesecond size, wherein each of the plurality of pixels includes at leastone sub-pixel disposed in the light emitting area, and wherein thesub-pixel comprises: a first electrode disposed on the substrate; anemission layer disposed on the first electrode; and a second electrodedisposed on the emission layer, wherein the sub-pixel emits onewavelength of light selected from the group of red light, green light,and blue light, wherein the first sensor is a touch sensor of aself-capacitance type or a touch sensor of a mutual-capacitance type,wherein the first sensor includes: a first touch electrode; and a secondtouch electrode spaced apart from the first touch electrode and forminga capacitance with the first touch electrode, and wherein each of thefirst touch electrode and the second touch electrode comprises a meshstructure.
 36. The display device of claim 35, further comprising aphoto sensor disposed in the first area below the substrate.
 37. Thedisplay device of claim 36, wherein a portion of the first sensor andthe first area are not overlapped in the plan view.
 38. The displaydevice of claim 35, wherein a portion of the first sensor and the firstarea are not overlapped in the plan view.